The Ecology and Classification of Rickettsia Species Phylotype G022, an Uncharacterized Bacterium from Ixodes pacificus Ticks

太平洋硬蜱未定性细菌立克次体种系型 G022 的生态学和分类

• 批准号: 10412445
• 负责人: Jianmin Zhong
• 金额: $ 14.75万
• 依托单位: HUMBOLDT STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-12 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10412445
• 关键词: Adult; Anaplasmosis; Animals; Arthropods; Bacteria; Biological Assay; Biology; Black-legged Tick; Bobcat; California; Canis familiaris; Cell Line; Centers for Disease Control and Prevention (U.S.); Classification; County; DNA; Dangerousness; Data; Diagnosis; Domestic Animals; Ecology; Educational Curriculum; Exanthema; Exposure to; Felis catus; Fever; Foxes; Funding; Genomics; Goals; Hispanic-serving Institution; Human; Infection; Ixodes; Ixodidae; Learning; Life; Low Prevalence; Lyme Disease; Medical; Methods; Molecular; Names; New Zealand; North America; Northern America; Nymph; Oryctolagus cuniculus; Outcome; Pathogenesis; Pathogenicity; Persons; Phylogenetic Analysis; Prevalence; Proteomics; Public Health; Publishing; Reporting; Research; Rickettsia; Rickettsia Infections; Route; Rural Community; Science; Students; Surveys; Symptoms; Tick-Borne Diseases; Ticks; Time; Training; Trees; United States; Universities; Work; blastomere structure; cost; detection method; experience; exposed human population; feeding; graduate student; human disease; infection rate; infection risk; insight; lower income families; next generation sequencing; novel; pathogen; serosurvey; spotted fever; success; tick bite; tick-borne; tick-borne pathogen; transmission process; undergraduate student; underrepresented minority student; vector

Project Summary/Abstract While both ticks and tick-borne disease agents have rapidly become a serious and growing threat to human and veterinary public health, mounting evidence indicates that many tick-borne diseases due to rickettsial infection may be under-reported in Northern America because of their uncharacteristic symptoms in humans and domestic animals. Ixodes pacificus is a principal vector for pathogenic and endosymbiotic bacteria on the Pacific West Coast of the United States. Compared to pathogenic rickettsiae identified in other tick species in California, the ecology and biology of pathogenic rickettsiae in I. pacificus remains largely unexplored. Our lab detected a novel Rickettsia species, Rickettsia species phylotype G022, in questing adult ticks of I. pacificus in three counties of Northern California in 2011, 2013, and 2020. Due to phylotype G022’s low prevalence (2-4.5%) in adult I. pacificus and published phylogenetic trees placing the bacterium within other pathogenic spotted fever group rickettsiae, our hypothesis is that phylotype G022 is a pathogenic Rickettsia. The proposed study ultimately serves as a continuation of our previous findings regarding the ecology and pathogenesis of Rickettsia species in I. pacificus. Our research pursues the following specific aims: 1) We will conduct a survey to estimate the prevalence of Rickettsia species phylotype G022 in nymphal ticks of I. pacificus by collecting the nymphs from the field and detecting the bacterium by real-time PCR; 2) We will study transmission routes of Rickettsia species phylotype G022 in I. pacificus by collecting all life stages of the ticks via feeding on New Zealand white rabbits and detecting the bacterium by real-time PCR; 3) We will perform the propagation and isolation of the Rickettsia phylotype G022 isolate from I. pacificus using tick embryonic cell lines and limiting dilution assay; 4) We will perform the molecular typing of the Rickettsia species phylotype G022 isolate by Multilocus Sequence Typing; 5) We will investigate the presence of Rickettsia species phylotype G022 infection in domestic dogs from Northern California. This study will not only result in the official naming of phylotype G022 by typing the pure bacterial isolate, but also enable us to start gathering data on transmission dynamics of the bacterium as well as its potential pathogenicity, the long-term research goal of our lab, to humans and animal hosts in Northern California.

项目摘要/摘要 虽然tick虫和tick虫疾病剂都迅速成为对人类和人类的日益严重威胁 兽医公共卫生，山的证据表明，由于身心感染引起的许多tick传播疾病可能是 由于人类和家畜的症状不明显，在美国北部报道的情况不足。 ixodes Pacificus是美国太平洋西海岸的致病性和内体细菌的主要载体。 与在加利福尼亚州其他壁虱物种中鉴定出的致病性人力体相比，致病性的生态学和生物学 I. Pacificus中的立克西亚仍然很出乎意料。我们的实验室检测到一种新颖的立克斯种类，立克物种 系统型G022，在2011年，2013年和2020年在北加州三个县的I. Pacificus的成人tick虫中。 由于系统型G022的低患病率（2-4.5％），成人I. Pacificus并发表了系统发育树，放置了 细菌在其他病原性斑点发烧组立克西亚（Rickettsiae）中，我们的假设是系统型G022是一种致病性 人力车。拟议的研究最终是我们先前关于生态学和的发现的延续 I. Pacificus中立克氏症的发病机理。我们的研究追求以下具体目标：1）我们将进行 调查通过收集I.太平洋的若虫tick虫中Rickettsia物种的流行率。 来自现场的若虫并通过实时PCR检测细菌； 2）我们将研究立克赛的传输路线 通过以新西兰白兔子为食来收集tick的所有生命阶段，在I. Pacificus中的物种类型G022 并通过实时PCR检测细菌； 3）我们将执行立克氏症的传播和隔离 使用tick胚胎细胞系和限制稀释测定法，从i。 4）我们将表演 人力体物种的分子型通过多焦点序列分型分离型G022分离物； 5）我们会的 研究了来自北加州的家犬中立体型G022感染的人力素型物种的存在。这 研究不仅会通过键入纯细菌分离株来导致系统型G022的正式命名，而且还可以使我们 为了开始收集有关细菌传播动力学及其潜在致病性的数据，长期 我们实验室的研究目标，北加州的人类和动物宿主。